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Type 2 diabetes (T2D) is a chronic metabolic disorder that has high comorbidity with mental disorders. The genetic relationships between T2D and depression are far from being well understood. We performed genetic correlation, polygenic overlap, Mendelian randomization (MR) analyses, cross-trait meta-analysis, and Bayesian colocalization analysis to assess genetic relationships between T2D and depression, in the forms of major depressive disorder (MDD) and depressed affect (DAF). Then, the summary data-based MR (SMR) analysis was performed to prioritize genes contributing to MDD and to T2D from functional perspective. MDD-driven signaling pathways were constructed to understand the influence of MDD on T2D at the molecular level. T2D has positive genetic correlations both with MDD (r Our study points out that depression, in the forms of MDD and DAF, may increase the risk of T2D. Analysis of underlying genetic variation and the molecular pathways, connecting depression and T2D, indicate that the pathophysiological foundations of these two conditions have a notable overlap. Show less

Although a giant Egyptian domestic non-migratory duck breed is phenotypically identical to the migratory Mallard, yet it is three times larger. The current study sought to determine the genetic and metabolic differences between this duck and Mallard, which arrives in Egypt in September for wintering and departs in March. Mitochondrial DNA control region (D-loop) was extracted, amplified, sequenced, and analyzed in both ducks. Both ducks were given a high-fat diet (HFD) for 6 weeks to assess their metabolic response to this diet. Polymorphism results indicated that the D-loop is highly variable and both populations expansion is balanced. The hierarchical analysis of molecular variants (AMOVA) and interpopulation difference parameters revealed significant genetic differentiation and minimal gene flow between migrant and resident populations. Phylogeny and Network analyses revealed that domestic ducks are a distinct group that separated from mallards. Physiologically, domestic duck blood and adipose tissue had a higher level of triglycerides and adipocyte volume than that of the depleting arriving migratory Mallard ducks, while leaving Mallard parameters were the highest, suggesting a high level of preparatory fat deposition and utilization before starting the trip. In response to HFD, the expression of FA uptake genes cd36, fabp1 was upregulated similarly in livers of domestic and migratory Mallard ducks, while the expression of lipid accumulation genes dgat2 and plin2 was higher in domestic than in migratory Mallards. However, the highest body mass and adipocytes volume gain was observed in the arriving migratory Mallards. In pectoral muscle, the expression of cd36 and fabp3 was higher in domestic than in leaving ducks, while in arriving Mallards, both genes were not upregulated in response to HFD. Dgat2 was upregulated only in domestic muscle, while lipid oxidation genes cpt1, lpl, and the controlling ppara were more upregulated in leaving Mallard. In conclusion, both ducks can be genetically and metabolically differentiated. Migratory mallards are more flexible and efficient in lipid metabolism than domestic ducks. Show less

Mitochondrial dysfunction is increasingly recognized as a key factor in neurodegenerative diseases (NDDs), underscoring the therapeutic potential of targeting mitochondria-related genes. This study aimed to identify novel biomarkers and drug targets for these diseases through a comprehensive analysis that integrated genome-wide Mendelian randomization (MR) with genes associated with mitochondrial function. Using existing publicly available genome-wide association studies (GWAS) summary statistics and comprehensive data on 1136 mitochondria-related genes, we initially identified a subset of genes related to mitochondrial function that exhibited significant associations with NDDs. We then conducted colocalization and summary-data-based Mendelian randomization (SMR) analyses using expression quantitative trait loci (eQTL) to validate the causal role of these candidate genes. Additionally, we assessed the druggability of the encoded proteins to prioritize potential therapeutic targets for further exploration. Genetically predicted levels of 10 genes were found to be significantly associated with the risk of NDDs. Elevated DMPK and LACTB2 levels were associated with increased Alzheimer's disease risk. Higher expression of NDUFAF2, BCKDK, and MALSU1, along with lower TTC19, raised Parkinson's disease risk. Higher ACLY levels were associated with both amyotrophic lateral sclerosis and multiple sclerosis (MS) risks, while decreased MCL1, TOP3A, and VWA8 levels raised MS risk. These genes primarily impact mitochondrial function and energy metabolism. Notably, several druggable protein targets identified are being explored for potential NDDs treatment. This data-driven MR study demonstrated the causal role of mitochondrial dysfunction in NDDs. Additionally, this study identified candidate genes that could serve as potential pharmacological targets for the prevention and treatment of NDDs. © 2025 International Parkinson and Movement Disorder Society. Show less

Colorectal cancer (CRC) is a fatal cancer prevalent worldwide, and epithelial-mesenchymal transition (EMT) is a key factor in tumor invasion and metastasis. Piperine, a natural alkaloid known for its antitumor properties, faces limitations in clinical use due to its moderate potency. To address this, our team synthesized and validated a new derivative, HJJ₃₅, which has shown potent antitumor activity against CRC cells. We assessed HJJ₃₅'s inhibitory effects on the colon cancer cell line HCT116 through MTT, colony formation, and assays for cell migration and invasion. To uncover HJJ₃₅'s molecular mechanisms, we utilized transcriptomics, weighted gene co-expression network analysis (WGCNA), and machine learning to identify key EMT-related genes. Western blot and immunofluorescence experiments confirmed the expression changes of these key proteins. Our findings indicate that HJJ₃₅ significantly suppressed the proliferation, migration, and invasion of HCT116 cells in vitro, outperforming piperine. We discovered that HJJ₃₅ downregulated the expression of COL12A1, PJA2, VCAN, MEF2C, DPYD, and DDR2 genes in HCT116 cells, which resulted in a decrease in the EMT regulator SNAI1, thus inhibiting EMT in these cells. In summary, this study presents novel evidence that the piperine derivative HJJ₃₅ inhibits the migration and invasion of colorectal cancer cells through SNAI1-mediated EMT. Show less

Exposure to environmental pollutants with obesogenic activity is being recognised as one of the contributing factors to the obesity epidemic. Bisphenol A (BPA) has been shown to stimulate adipogenesis in both human and mouse preadipocytes, to increase body weight and affect lipid metabolism in animal and epidemiological studies. Regulatory action and public concern has prompted industry to replace BPA with other structurally similar analogues that may have similar effects. In this study we investigated the effects of fifteen BPA analogues on adipogenesis in the mouse 3 T3-L1 pre-adipocyte cell model in order to determine their adipogenic activity relative to BPA. 3 T3-L1 cells were treated with increasing concentrations of BPA and replacements and mRNA expression of the mature adipocyte markers fatty acid binding protein 4 (Fabp4), perilipin (Plin) lipoprotein lipase (Lpl)and peroxisome proliferator-activated receptor (Ppar)γ and lipid accumulation were assessed. In addition, a luciferase reporter assay for PPARγ transactivation was employed to investigate mechanism of action. Our results show that BPC, BPS-MAE, BPS-MPE and TGSA, were the most adipogenic bisphenols, as shown by a robust increase in lipid accumulation and mRNA expression of adipogenic markers. BPS-MPE, BPC, BTUM, TGSA and D8 increased PPARγ transcriptional activity. Despite its ability to activate PPARγ in the transcriptional assay D8 did not affect adipogenesis in this cell model. Show less

Biomarker profiling from biofluids such as blood are widely measured in clinical research, using for example Olink proteomics panels. One such research focus area is cardiovascular disease (CVD), for which chronic sleep restriction (SR) is a risk factor. However, it remains unclear whether blood levels of commonly measured CVD biomarkers are sensitive to acute dynamic factors such as SR, physical exercise (PEx), and time of day. In this crossover design, 16 normal-weight, healthy men underwent three highly standardized in-lab nights of SR (4.25 h/night) and normal sleep (NS, 8.5 h/night) in randomized order, with 88 CVD blood protein biomarkers quantified using the Olink technology (and selected validation using ELISA) in the morning, evening, and immediately before and repeatedly after 30 min of high-intensity exercise. We found significant time-of-day-dependent changes in several CVD biomarkers. Whereas several proteins were exercise-induced across sleep conditions (such as the canonical exerkines IL- 6 and BDNF), exercise-induced proteomic dynamics differed in response to recurrent SR, compared with following NS. Moreover, SR compared with NS resulted in a biomarker profile previously associated with increased prospective risk of several CVDs across large-scale cohorts (such as higher circulating levels of IL-27 and LGALS9). Our findings highlight how dynamic physiology can modulate CVD biomarker levels. These results also underscore the need to consider sleep duration as a key determinant of cardiovascular health-an emphasis reflected in recent American Heart Association guidelines. Further studies in women, older individuals, and patients with prior CVD, and across different chronotypes and dietary schedules are warranted. Show less

Strong T cell receptor (TCR) and interleukin (IL)-27 signaling influence type 1 regulatory (Tr1) T cell development, but whether other signals determine their differentiation is unclear. Utilizing Tg4 TCR transgenic mice, we established a model for rapid Tr1 cell induction. A single high dose of [4Y]-MBP peptide drove the differentiation of Show less

Psychosocial stress has been linked to myriad mental and physical health conditions. Stress-induced changes to functioning of the immune system is a plausible mechanism in this association. Psychosocial stress is a well-established contributor to immune dysregulation, though the extant literature to date falls short of addressing the role of distal relative to contemporary stress in immune function, particularly as they relate to distinctions between innate and adaptive immunity. The present study directly addressed this knowledge gap by characterizing vertically-integrated markers of immune functioning as a function of both recent chronic stress during adolescence and childhood adversity. In the present study, childhood adversity (before age 10) and recent psychosocial stressors (past 6 months) were characterized via semi-structured clinical interviews among 127 adolescent girls (aged 13-17; 31 % Black, 38 % Hispanic, 32 % NHW) who have all measures included in this report. Vertically-integrated markers of immune activity were also collected: an a priori subset of immune-related genes using genome-wide transcriptional profiling, an 11-plex of circulating cytokines (IL-6, TNF-α, IL-10, IL-8, IFN-γ, IL-1β, IL-1α, IL-27, MCP-1, IL-12p70, IP-10), and systemic inflammation (C-reactive protein; CRP). The association between recent chronic stress and intracellular immune outcomes differed based on childhood adversity. Genome-wide transcriptional profiling implicated myeloid lineage cells, specifically monocytes and dendritic cells, in differential patterns of gene expression among childhood adversity-exposed youth in the context of chronic stress. These differential patterns were also reflected in expression of proinflammatory genes and CRP such that among adolescents without exposure to childhood adversity, more recent chronic stress was associated with less proinflammatory gene expression, b = -0.45 (SE = 0.22), p = 0.04, 95 %CI [-0.87, -0.02], and somewhat higher CRP, b = 0.62 (SE = 0.35), p = 0.08, 95 %CI [-0.07, 1.31], while among adolescents with exposure to childhood adversity, more recent chronic stress was not associated with any immune activity markers. However, these patterns among circulating markers did not survive corrections for multiple comparisons. Immune adaptation in the context of chronic stress may indicate plasticity to environmental demands that conserves biological resources, which may be a source of resilience that is negatively impacted by childhood adversity. Show less

The melanocortin 4 receptor (MC4R) plays a critical role in satiety and energy homeostasis, and its dysregulation is implicated in numerous hyperphagic and obese disease states. Setmelanotide, a disulfide-based cyclic peptide, can rescue MC4R activity and treat obesities caused by genetic defects in MC4R signaling. But this peptide has moderate blood-brain barrier penetrance and metabolic stability, which can limit its efficacy in practice. Based on the cryo-electron microscopy structure of setmelanotide-bound MC4R, we hypothesized that replacing its lone disulfide bond with more metabolically stable and permeability-enhancing carbon-based linker groups could improve pharmacokinetic properties without abolishing activity. To test this, we used chemistry developed by our lab to prepare 11 carbocyclic (alkyl, aryl, perfluoroalkyl, and ethereal) analogs of setmelanotide and determined their biochemical potencies at MC4R in vitro. Ten analogs displayed full agonism, showing that disulfide replacement is tolerant of linkers ranging in size, rigidity, and functional groups, with heteroatom- or aryl-rich linkers displaying superior potencies. Show less

Hypoactive sexual desire disorder (HSDD) is the most reported sexual dysfunction among premenopausal women worldwide. Bremelanotide, trade name Vyleesi, has been approved by the United States Food and Drug Administration to treat HSDD. However, despite approval, very little is known about its neurobiological mechanism of action. In this study, we utilized a female Syrian hamster model to investigate the effects of bremelanotide on melanocortin receptor expression in the mesolimbic dopamine system and sexual reward. We found that the majority of melanocortin 3 and 4 (MC4R) receptor mRNA is expressed in dopamine neurons in the ventral tegmental area (VTA). Fewer neurons express MC4R in the nucleus accumbens (NAc) or dorsal striatum, where they rarely colocalize with neurons expressing dopamine D1 or D2 receptors. Instead, MC4R mRNA is expressed in nucleus accumbens interneurons. Neither the low nor the high dose of bremelanotide had an effect on the expression of melanocortin receptor mRNA in the mesolimbic dopamine system. Finally, sexual experience resulted in a conditioned place preference (CPP) in female Syrian hamsters, though bremelanotide treatment failed to enhance sexual reward in this test. The results of this study are discussed in conjunction with similar studies in rats, with the conclusion that bremelanotide does not act on the VTA-NAc reward circuit and does not enhance the rewarding effects of sexual interactions. Show less

Excessive inflammation in sepsis causes microvascular dysfunction associated with organ dysfunction and high mortality. The present studies aimed to examine the therapeutic potential of linagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor in a clinically relevant polymicrobial sepsis model in mice. Sepsis was induced by cecal ligation and puncture (CLP). Mice were grouped into: Sham control+vehicle; Group 2: CLP+vehicle; Group 3: CLP+dexamethasone (10 mg/kg, s.c.) given 6 h after CLP; Group 4: CLP+linagliptin (1 mg/kg, s.c.) given 6 h after CLP. The experiment was terminated 24 hours after CLP in two experimental sets. Seven-day survival following CLP was determined in a third experimental set. Treatment with linagliptin inhibited DPP-4 activity, increased the levels of active forms of endogenous gastric inhibitory polypeptide and glucagon-like peptide-1, without affecting the blood glucose levels in CLP mice. Compared to vehicle treatment, administration of linagliptin reduced sepsis-induced tissue hyper permeability as evidenced by a reduction in vascular Evans blue leakage, prevented edema formation in the lung, heart, liver and kidney. Furthermore, linagliptin or dexamethasone reduced sepsis-induced proinflammatory cytokine and chemokine production, such as IL-1β, IL-2, IL-10, IL-23, IL-27, VCAM-1, eotaxin, MDC, MCSF1, GCP-2, and NGAL. Importantly, administration of linagliptin improved the 7-day survival rate following CLP in mice. RNA sequencing in lung and heart revealed that linagliptin attenuated key inflammatory pathways including TNF alpha (via NFκB) and IL6/JAK/STAT3 signaling and activated interferon signaling in the heart. Linagliptin treatment can attenuate the inflammatory response, protect against severe sepsis-induced vascular hyperpermeability, reduce multiorgan injury, and most importantly, improve the survival. Show less

The melanocortin-4 receptor (MC4R) is a G protein-coupled receptor expressed at hypothalamic neurons that has an important role in appetite suppression and food intake. Mutations in MC4R are the most common cause of monogenic obesity and can affect multiple signaling pathways including Gs-cAMP, Gq, ERK1/2, β-arrestin recruitment, internalization and cell surface expression. The melanocortin-2 receptor accessory protein 2 (MRAP2), is a single-pass transmembrane protein that interacts with and regulates signaling by MC4R. Variants in MRAP2 have also been identified in overweight and obese individuals. However, functional studies that have only measured the effect of MRAP2 variants on MC4R-mediated cAMP signaling have produced inconsistent findings and most do not reduce MC4R function. Here we investigated the effect of twelve of these previously reported MRAP2 variants and showed that all variants that have been identified in overweight or obese individuals impair MC4R function. When expressed at equal concentrations, seven MRAP2 variants impaired MC4R-mediated cAMP signaling, while nine variants impaired IP3 signaling. Four mutations in the MRAP2 C-terminus affected internalization. MRAP2 variants had no effect on total or cell surface expression of either the MRAP2 or MC4R proteins. Structural models predicted that MRAP2 interacts with MC4R transmembrane helices 5 and 6, and mutations in two MRAP2 residues in putative contact sites impaired the ability of MRAP2 to facilitate MC4R signaling. In summary, our studies demonstrate that human MRAP2 variants associated with obesity impair multiple MC4R signaling pathways and that both Gs-cAMP and Gq-IP3 pathways should be assessed to determine variant pathogenicity. Show less

Amphetamine (AMPH) exerts metabolic and cardiovascular effects. The central melanocortin system is a key regulator of both metabolic and cardiovascular functions. Here, we show that the melanocortin system partially mediates AMPH-induced anorexia, energy expenditure, tachycardia, and hypertension. AMPH increased α-melanocyte stimulating hormone (αMSH) secretion from the hypothalamus, elevated blood pressure and heart rate (HR), increased brown adipose tissue (BAT) thermogenesis, and reduced both food intake (FI) and body weight (BW). In melanocortin 4 receptor-deficient (MC4R knockout [KO]) mice, metabolic and cardiovascular effects of AMPH were significantly attenuated. Antagonism of serotonergic and noradrenergic neurotransmitter systems attenuated AMPH-induced αMSH secretion as well as AMPH-induced metabolic and cardiovascular effects. We propose that AMPH increases serotonergic activation of proopiomelanocortin (POMC) neurons and reduces the noradrenergic inhibition of POMC neurons, thereby disinhibiting them. Together, these presynaptic mechanisms result in increased POMC activity, increased αMSH secretion, and increased activation of MC4R pathways that regulate both the metabolic and cardiovascular systems. Show less

The G protein-coupled receptor (GPCR) melanocortin receptor 4 (MC4R) is an essential regulator of body weight homeostasis. MC4R is unusual among GPCRs in that its activity is regulated by 2 opposing physiological ligands, the agonist ⍺-MSH and the antagonist/inverse agonist AgRP. Paradoxically, while MC4R localizes and functions at the cilium of hypothalamic neurons, the ciliary levels of MC4R are very low under unrestricted feeding conditions. Here, we find that the constitutive activity of MC4R is responsible for the continuous depletion of MC4R from cilia and that inhibition of MC4R's activity via AgRP leads to a robust accumulation of MC4R in cilia. Ciliary targeting of MC4R is mediated by its partner MRAP2 and the constitutive exit of MC4R from cilia relies on the sensor of activation β-arrestin, on ubiquitination, and on the BBSome ciliary trafficking complex. Thus, while MC4R exits cilia via conventional mechanisms, it only accumulates in cilia when its activity is suppressed by AgRP. Show less

Epilepsy, affecting millions globally, often leads to significant cognitive and psychiatric comorbidities, particularly in children. Anxiety and depression are particularly prevalent, with roughly a quarter of pediatric epilepsy patients having a comorbid diagnosis. Current treatments inadequately address these issues. Adrenocorticotropic hormone (ACTH), a melanocortin peptide, has shown promise in mitigating deficits after early-life seizures (ELS), potentially through mechanisms beyond its canonical action on the melanocortin 2 receptor. This study explores the hypothesis that recurrent ELS is associated with long-term anxiety and that treatment with ACTH can prevent this anxiety through a mechanism that involves the melanocortin 4 receptor (MC4R) in the brain. Our findings reveal that ACTH ameliorates anxiety-like behavior associated with ELS, without altering seizure parameters, in wild-type but not in male and female MC4R knock-out mice. Our findings also show that knocking-in MC4R in either neurons or astrocytes was able to rescue the anxiety-like behavior after ACTH treatment. Furthermore, our results show that ACTH normalizes important astrocytic proteins like glial fibrillary acidic protein and aquaporin-4 after ELS. This suggests that ACTH's beneficial effects on anxiety are mediated through MC4R activation in both neuronal and astrocytic populations. This study underscores the therapeutic potential of targeting MC4R as a treatment, highlighting its role in mitigating anxiety-like behaviors associated with ELS. Show less

Genetic obesity results from loss-of-function mutations, including those affecting the leptin-melanocortin system, which regulates body weight. Pro-opiomelanocortin (POMC)-derived neurohormones act as ligands for melanocortin receptors (MCRs), regulating the leptin-melanocortin pathway through protein-protein interactions. Loss-of-function mutations in the genes encoding POMC, MC3R, and MC4R can lead to the dysregulation of energy expenditure and feeding balance, early-onset obesity, and developmental dysregulation. Recent studies have identified new genetic regulatory mechanisms and potential biomarker regions for the Show less

Multiple sclerosis (MS) is a multifaceted neurodegenerative disorder influenced by genetics and lifestyle. This systematic literature review investigates the role of six obesity-associated genes, including fat mass and obesity-associated (FTO), FAS apoptosis inhibitory molecule 2 (FAIM2), Niemann-Pick disease type C1-like 1 (NPC1), glucosamine-6-phosphate deaminase 2 (GNPDA2), melanocortin-4 receptor (MC4R), and brain-derived neurotrophic factor (BDNF) in the context of MS. A literature search was executed using Embase, Scopus, Cochrane, Web of Science, and PubMed databases from inception to July 2024. The related keywords employed during the search process are "fas apoptotic inhibitory molecule 2," "Niemann-Pick disease type C1," "fat mass and obesity-associated," "melanocortin-4 receptor," "brain-derived neurotrophic factor," "glucosamine-6-phosphate deaminase 2," and "multiple sclerosis." Out of 2108 papers, 27 were entered into the present systematic literature review. The FTO gene may affect MS susceptibility through metabolic and inflammatory pathways. FAIM2 and NPC1 genes may contribute to MS pathogenesis, though their precise roles are still being elucidated. The GNPDA2 gene may have some connections with MS but requires further clarification. MC4R has demonstrated significant neuroprotective and anti-inflammatory effects, suggesting its potential impact on MS progression. BDNF plays a complex role in neuronal survival and repair and may influence the risk of MS. Our findings demonstrated that obesity-related genes may have a significant impact on MS risk and disease course, revealing novel insights into the genetic underpinnings of MS. Show less

Bardet-Biedl syndrome (BBS) is a rare, genetically heterogeneous, and highly pleiotropic autosomal recessive ciliopathy. Patients typically present with early loss of vision, hyperphagia, severe obesity, learning difficulties, and renal dysfunction. In patients with BBS, dysfunction of the immotile primary cilia in the hypothalamic melanocortin-4 receptor (MC4R) pathway responsible for controlling energy balance, hunger, and satiety results in severe hyperphagia manifesting in food-seeking behaviors that drive the development of obesity early in childhood. These behaviors have negative impacts on many areas of the lives of patients with BBS and their families/caregivers, including sleep, mood, school/work, and social/family relationships. Additionally, many patients feel stigmatized due to their hyperphagia-associated food-seeking behaviors and the resulting obesity, which exacerbates the impacts of hyperphagia on quality of life. Early identification and management of hyperphagia in patients with BBS is key: mitigating food-seeking and weight gain can improve quality of life and reduce the risk of metabolic and cardiovascular diseases that is increased in patients with BBS. Until recently, the only treatment strategies available were lifestyle and diet modifications. However, targeted treatment with the novel MC4R agonist setmelanotide now offers an effective management option to reduce hyperphagia and weight in patients with BBS, improving overall health and quality of life. Show less

The dopaminergic system is crucial for affect regulation. Melanocortin 4 receptors (MC4R) in the ventral striatum have been shown to be necessary for establishing aversive states. Here, we functionally characterize MC4R-expressing striatal neurons in mice. MC4Rs were enriched in atypical dopamine receptor 1 (D1) neurons in the lateral stripe of the striatum (LSS), an understudied area in the ventrolateral striatum. Fiber photometry recordings showed that MC4R neuron activity and local dopamine release in the LSS increased in response to both rewarding and aversive stimuli. Moreover, MC4R neuronal activity and glutamate release in the LSS correlated with body movement. Optogenetic activation of MC4R-LSS neurons was rewarding in a real-time place preference test and a self-stimulation paradigm, increased locomotor activity, and induced striatal dopamine release. Collectively, our findings suggest that MC4R-LSS neurons are activated by stimuli of both rewarding and aversive character and that they induce positive affect, dopamine release and locomotion. Show less

This study aimed to investigate the genetic etiology and clinical features of non-syndromic pediatric obesity in a large Chinese cohort, providing insights into the genetic profile and its correlation with clinical phenotypes. We enrolled 391 children, aged 7-14 years, diagnosed with non-syndromic pediatric obesity at Jiangxi Provincial Children's Hospital from January 2020 to June 2022. Whole-exome sequencing was employed to identify potential genetic causes, focusing on 79 candidate genes associated with obesity. Multivariate logistic regression analysis was performed on the clinical data of the non-syndromic obesity gene-positive group and the gene-negative group. Among the 391 patients, 32 (8.2%) carried 18 non-syndromic obesity genes, with UCP3 and MC4R being the most common. Seven cases (1.8%) were rated as likely pathogenic by the American College of Medical Genetics and Genomics (ACMG). Clinical phenotype and genetic correlation analysis revealed that urinary microalbumin, fT4, GGT, uric acid, serum phosphorus, paternal weight, family history, impaired glucose tolerance (IGT), non-HDL cholesterol (non-HDL-C), and metabolic syndrome (MetS) showed significant statistical differences (P < 0.05). Serum phosphorus is an independent risk factor associated with genetic predispositions to obesity in children and adolescents (P < 0.05). Our findings highlight the genetic heterogeneity of non-syndromic pediatric obesity and identify UCP3 and MC4R as potential hotspot genes in the Chinese population. The study underscores the potential of genetic testing for early diagnosis and personalized management of pediatric obesity. Show less

Characteristics of hyperphagia include heightened and prolonged hunger, longer time to satiation, shorter duration of satiety, severe preoccupation with food (i.e., hyperphagic drive), abnormal food-seeking behaviors, and distress or functional impairment when food is unavailable. Patients with melanocortin-4 receptor (MC4R) pathway diseases including those caused by variants in one of multiple key genes of the pathway often present with hyperphagia that results in early-onset, severe obesity because this pathway plays a critical role in regulation of hunger/satiation and energy balance. Patients with syndromic obesity (e.g., Bardet-Biedl syndrome) may also have hyperphagia as a result of neurodevelopmental disruptions in the MC4R pathway. Genetic testing is suggested in patients with early-onset, severe obesity and clinical features of genetic obesity (e.g., hyperphagia, neurodevelopmental differences, dysmorphic features); however, only a small percentage of individuals who meet these criteria undergo testing, potentially owing to limited availability, overlapping symptoms with other obesity types, and infrequent use of genetic testing during diagnosis. Diagnosing hyperphagia may be challenging, as no guidelines have been established for individuals with MC4R pathway diseases. Identifying these individuals is crucial to addressing the challenges of hyperphagia and associated obesity, which often limit quality of life and place overwhelming burdens on patients and families. Show less

This review examines the role of adipokines and gene polymorphisms in the development of depression and obesity. It is of great importance to understand the mechanisms that may be effective in the development of obesity and depression as their incidence increases. Adipokines are released from adipose tissues and primarily regulate the connection between the metabolic and inflammatory effects of obesity and the brain cells and adipose tissue. Adipokines may potentially contribute to the pathophysiology of depression by influencing the HPA axis and neurotransmitters. According to some estimates, the genetic overlap between obesity and depression is as high as 12 percent. Furthermore, these genes may be linked to significant interconnected signaling networks that have a role in the etiology of both disorders. Obesity and depression are both on the rise globally, and it is thought that there is a bidirectional relationship between these two conditions. Obesity and obesity-induced depression seriously limit the psychosocial functionality of individuals and impair their quality of life. Having a high body mass index (BMI) raises the likelihood of developing depression. On the other hand, as the BMI elevates in people suffering from depression, the possibility of developing obesity also rises. Show less

Incretin mimetics, especially dual/triple agonists, are effective for type 2 diabetes and obesity, though mechanisms remain unclear. This study applied PET using [ In vitro binding assays on frozen HEK293 cell sections overexpressing human GLP-1R, GIPR, or GCGR assessed [ [ PET imaging in pigs demonstrated in vivo GLP-1R engagement by SAR441255 and tirzepatide, and GIPR engagement by SAR441255 in the pancreas. SAR441255 exhibited dose-dependent GLP-1R occupancy in the pancreas and brain regions linked to appetite regulation. The study was funded by Uppsala Diabetes Center, Diabetesfonden, ExoDiab, Diabetes Wellness Sweden, Barndiabetesfonden, Science for Life Laboratory, and the Swedish Research Council. Show less

Chronic cold exposure in mice increases metabolic demand and food intake; the gut correspondingly expands its absorptive surface area. Gut enteroendocrine cells produce peptide hormones including glucagon-like peptide-1 (GLP-1), GLP-2, and glucose-dependent insulinotropic polypeptide (GIP) in response to a meal to facilitate nutrient absorption and post-prandial metabolism. The requirement of GLP-1, GLP-2, and GIP receptor signaling for small intestinal adaptations to chronic cold stress has not been investigated. Here, we show that male and female wild-type, double incretin receptor knockout (Glp1r Show less

Multi-target peptide therapeutics targeting glucagon receptor (GCGR), glucagon-like peptide-1 receptor (GLP1R), and glucose-dependent insulinotropic polypeptide receptor (GIPR) represent a promising approach for treating diabetes and obesity. Triple agonist peptides demonstrate promising therapeutic potential compared to single-target approaches, yet rational design remains computationally challenging due to complex sequence-structure activity relationships. Existing methods, primarily based on convolutional neural networks, impose limitations including fixed sequence lengths and inadequate representation of molecular topology. Graph Attention Networks (GAT) offer advantages in capturing molecular structures and variable-length peptide sequences while providing interpretable insights into receptor-specific binding determinants. A dataset of 234 peptide sequences with experimentally determined binding affinities was compiled from multiple sources. Peptides were represented as molecular graphs with seven-dimensional node features encoding physicochemical properties and positional information. The GAT architecture employed a shared encoder with task-specific prediction heads, implementing transfer learning to address limited GIPR training data. Performance was evaluated using 5-fold cross-validation and independent validation on 24 literature-derived sequences. A genetic algorithm framework was developed for peptide sequence optimization, incorporating multi objective fitness evaluation based on predicted binding affinity, biological plausibility, and sequence novelty. Cross-validation demonstrated robust GAT performance across all receptors, with GCGR achieving high accuracy (AUC ROC: 0.915 ± 0.050), followed by GLP1R (AUC-ROC: 0.853 ± 0.059), and GIPR showing acceptable performance despite limited data (AUC-ROC: 0.907 ± 0.083). Comparative analysis revealed receptor-specific advantages: GAT significantly outperformed CNN for GCGR prediction (RMSE: 0.942 vs. 1.209, p = 0.0013), while CNN maintained superior GLP1R performance (RMSE: 0.552 vs. 0.723). Genetic algorithm optimization measurable improvement over baseline, with 4.0% fitness Enhancement and generation of 20 candidates exhibiting mean binding probabilities exceeding 0.5 across all targets. The GAT-based framework provides a computational approach in computational peptide design, demonstrating receptor-specific advantages and robust optimization capabilities. Genetic algorithm optimization enables systematic exploration of sequence space within existing agonist scaffolds while maintaining biological constraints. This approach provides a rational framework for prioritizing experimental validation efforts in triple agonist development. Show less

Leptin resistance limits anti-obesity efficacy. We identified a leptin-sensitizing mechanism through tirzepatide (TZP), a glucagon-like peptide-1 receptor (GLP-1R) and glucose-dependent insulinotropic polypeptide receptor (GIPR) dual-agonist. Our tirzepatide clinical trial revealed that circulating leptin levels at baseline correlated with weight loss efficacy in patients with obesity, suggesting leptin and tirzepatide could interact to achieve stronger effects on weight loss. Next, we utilized the diet-induced obesity (DIO) mice and demonstrated the synergistic effects of tirzepatide and leptin combination (TZP+Lep) on weight loss. TZP+Lep treatment further improved hepatic insulin sensitivity and upregulated thermogenetic gene expression in brown adipose tissue. Metabolic profiling under thermoneutrality revealed TZP+Lep treatment further reduced food intake and increased energy expenditure. Tirzepatide sensitized leptin signaling in hypothalamic pro-opiomelanocortin (POMC) and GLP-1R expressing neurons. TZP+Lep synergistically increased POMC neuronal firing by decreasing the inhibitory postsynaptic input. Together, our work showed combining tirzepatide and leptin as a potential way for better maintenance of metabolic homeostasis in obesity management. Show less